The present invention relates in general to a device for detecting unacceptable defects in hollow glass articles. Devices of the above-mentioned general type are known in the art. One known device is disclosed, for example, in the German Offenlegungsschrift No. 29 16 361. In this device a light source is formed by a plurality of flashlights which are arranged in a circle coaxial with a test piece located in a measuring position. In each testing cycle, all flashlights are simultaneously actuated by a light barrier reacting to the presence of the test piece, and they are actuated in a single action. The flash beam passes through a ring-shaped dispersion disk located outwardly of an image tube and partially impinges on the top surface of the mouth or neck of the test piece. From there a portion of the light beam is reflected into the interior of the image tube and received by a television camera arranged at the upper end of the image tube and operating in accordance with a light-scanning method. Thereby a charge image is formed on a light-sensitive layer of the tube of the television camera, which corresponds to the image of the upper surface of the neck of the glass article. This charge image is stored and later on is evaluated in an interpreting circuit. Until then, the scanning beam of the camera tube must be blocked to prevent a premature extinction of the stored charge image. From the pairs of pulses resulting during the line-by-line scanning of the charge image, chordal length signals are produced and compared with nominal value signals. If a deviation from a preset value is detected, a fault signal is generated and used for actuation of an ejector. The devices for producing, visualization, and interpreting of these fault signals are relatively uncertain and complicated and can be serviced and repaired by specially trained staff which is normally not available in glassworks, particularly in developing countries. This staff is not readily available, as compared with the conventional staff in the glassworks, to accept indispensible late, and night shifts. Moreover, the known testing device can detect only a defective sealing face of the neck of glass articles.
The pamphlet "Kombi-Inspektor Typ 64" 3000 d.9/77 of Hermann Kronseder, Maschinenfabrik, D-8402 Neutraubling, describes a bottom inspection of bottles. The bottles are illuminated by an illuminating device from below. Beams pass through the neck of the bottle and optical means in a light divider, and the latter deflects a part of the beam at a right angle and deflects it through optical means onto a hexagonal flat light-emitting diode array for inspecting the bottle bottom center.